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Re: I'm just not sure about one thing

"First of all, we have your idea of "natural" sound, which has not been verified"

True and the same can be said for when you say your system sounds fine as well. However; are you a regular goer of live classical and/or other music that is unamplified? Are you a musician or have you lived with someone who is a professional musician? Do you now or have you ever been involved in the making of recordings in natural spaces (ie. a concert hall)? If you answer yes to these then I perhaps we are coming from the same background.

"Second, in real life, sounds farther off are often softer but have more reflected sound."

Yes this is correct; however, we are discussing the systems effects on sounds that were recorded from farther away or that are soft but close. You don't want the system to impose the same effect as a live sound from far away. It is like a double negative, its a no no!

"Third, turning the volume down often makes the stereo image seem to move back some."

Why should this be? Is this simply your observation in your system or do you have some physical explanation? If the system is properly preserving the harmonic content of the instruments when you decrease the volume then it shouldn't happen. With a real instrument, like a sax or trumpet, the sound recedes more inside the instrument at lower volumes than when it is played full blast. This has a lot to do with how the harmonic content of the instrument changes with the volume level its played at.

If I understand you correctly you are saying that a loud trumpet (as it is on the recording) played back softly (as in the volume control turned down) will sound farther away than it would if the volume control was set to give a realistic SPL level. IMO, this is a clear sign that your system has a different set of harmonic components that it adds at the low level vs. the high level or the speakers FR balance is different at low spl level vs. high spl level. Either way this would seem to indicate a problem with that system. I don't disagree that this receding of the sound with decreasing level could happen just that it should not happen.

"Fourth, like it or not, at lower volumes, the ear is less sensitive to low and high frequencies."

No one is disputing this. However; the microphone doesn't suffer from this problem, which means that soft sounds are captured with close to the original harmonic content and freqeuency balance. The reproduction will then sound natural (ie. you will hear the same content on the recording that you would have heard live if you were there) IF the system is not further altering the harmonic content and FR with level. If it is, namely losing bass and HF response at low levels, then the sound will lose life at low levels and no longer sound realistic. As long as these are preserved at low levels it will sound like a natural softening not the usual lifelessness most systems exhibit.

For example, whenever a reviewer says a speaker needs some juice to "wake up" this is a clear sign to me that this speaker cannot perform naturally with low level signals, this means either when played at low volumes or when there are soft sounds (like ambient information) in the louder matrix of the music.

"Many posters here besides my self have suggested that speakers which sound good at low volumes tend to approximate the Fletcher-Munson curves (or someone else's equal loudness curve)."

Maybe they are purposely designed this way to compensate for the losses that typical speakers show at low levels (the losses are always there just more noticeable at low levels where the percentage of error is larger). However; now this speaker will not sound correct at higher volumes because the bass and treble are tipped up. Manipulating frequency response is not really the answer to what is really a loss of dynamics. The only way I can think to do this in the frequency domain is with DSP where the DSP monitors the current to drivers and then applies a sliding scale equalization curve dependent on the signal level. It can be fast enough but I don't know anyone making a level dependent equalizer. Maybe a bright idea though.

It is the same problem with Class AB amps. They have zero crossing distortion that makes itself most known at low levels and is a major reason why these amps don't sound good at low levels because the distortion to signal ratio is much greater than at full power. The zero distoriton is always the same in absolute level terms.

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